How to fix undefined POST index from AJAX?

Question

I'm sending an ajax "POST" in my php file. But the problem is the index of the POST is undefined.

This is my sample code in ajax.

$(".add-percentage").click(function(){

    var percentage_id = $(this).data('landing_id-percentage');

    $.ajax({
        url: 'ajax/readPercentage.php',
        type: 'POST',
        data: { percentage_id : percentage_id },
        success: function(data) {
          alert(data);
        },
        error: function(request, status, error){
          alert("Error!! "+error);
        }             
  });
});

My php code having an undefined index POST..

if(isset($_POST['percentage_id'])){

   $percentage_id = $_POST['percentage_id'];

   $query = mysqli_query($conn, "SELECT * FROM percentage WHERE percentage.percentage_id = '$percentage_id'");
}else{
  echo "Index is not properly set!";
}

I hope someone can help me. Thanks in advance.

You are getting a notice or `Index is not properly set!`? Your SQL is open to injections. — user3783243, Oct 22 '18 at 03:01
@user3783243 yes bro i'm getting a notice that the index is undefined. — Unus Instar Omnium, Oct 22 '18 at 03:15
Check this: https://stackoverflow.com/questions/8945879/how-to-get-body-of-a-post-in-php. You can't access request's data, in `REST`, using `$_POST`. You should use `php://input`. — Salim Ibrohimi, Oct 22 '18 at 03:27
@SalimIbrogimov Can you post an answer? I don't follow how the `isset` is true. — user3783243, Oct 22 '18 at 03:41
your code works just fine without any change. try to debug in console that will give you more details. — prasanna puttaswamy, Oct 22 '18 at 04:23
your js and php seems good try debugging the value of `$(this).data('landing_id-percentage')` check if really returns a valid value not an undefined — Beginner, Oct 22 '18 at 05:30

score 0 · Answer 1 · answered Oct 22 '18 at 03:49

0

if($_SERVER['REQUEST_METHOD']=="POST"){
   $data = file_get_contents('php://input');
   print_r($data); // for testing purpose.

   /*
   $query = mysqli_query($conn, "SELECT * FROM percentage WHERE percentage.percentage_id = $data[0]['pecentage_id']");
   */
}else{
  echo "Index is not properly set!";
}

answered Oct 22 '18 at 03:49

Salim Ibrohimi

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Bro when the success: function(data) { alert(data); }, the values are displayed but in the php file is not being displayed is returns else statement. – Unus Instar Omnium Oct 22 '18 at 04:04
yes bro I tried the code above it will return else statement. – Unus Instar Omnium Oct 22 '18 at 04:10
@UnusInstarOmnium you have an issue in your AJAX request. Your API expects for POST request, `if($_SERVER['REQUEST_METHOD']=="POST")`. Use `Postman` to check your API, https://www.getpostman.com/. – Salim Ibrohimi Oct 22 '18 at 04:27
bro @Salim Ibrogimov, when I alert the data from php response the output data is Array([landing_id]=>7) but when in displaying the print_r($_POST); from the php the output data is Array( ). – Unus Instar Omnium Oct 22 '18 at 10:02
bro @Salim Ibrogimov, when I reload the whole page the readPercentage.php is already undefined the index percentage_id. Then when I submit the data from ajax the php POST did not received the data and it display Array( ). What is the possible problem of this? – Unus Instar Omnium Oct 22 '18 at 10:27
@UnusInstarOmnium I told you, you can't retrieve POST request's data via `$_POST`. You should try this: `$data = file_get_contents('php://input'); print_r($data);`. – Salim Ibrohimi Oct 23 '18 at 03:13

Maulik patel · Answer 2 · 2018-10-22T04:08:21.667

Please use this code for ajax

$(".add-percentage").click(function(){

    var percentage_id = $(this).data('landing_id-percentage');

    $.ajax({
        url: 'ajax/readPercentage.php',
        type: 'POST',
        dataType: 'json',
        data: { percentage_id : percentage_id },
        success: function(data) {
          alert(data.status);
        },
        error: function(request, status, error){
          alert("Error!! "+error);
        }             
  });
});


<?php
$result_array= array();
if(isset($_POST['percentage_id'])){

   $percentage_id = $_POST['percentage_id'];
   $select_query = "SELECT * FROM percentage WHERE percentage.percentage_id =".$percentage_id;

   $query = mysqli_query($conn,$select_query);
   $result_array['status'] = 'success';
   $result_array['success_msg'] = 'Data get successfully';
}else{
  //echo "Index is not properly set!";
  $result_array['status'] = 'failure';
  $result_array['error_msg'] = 'Index is not properly set!';
}
echo json_encode($result_array);
    die();
?>

its ok the alert message is success. – Unus Instar Omnium Oct 22 '18 at 04:39 — Unus Instar Omnium, Oct 22 '18 at 04:39

How to fix undefined POST index from AJAX?

2 Answers2